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The genus Capronia includes a number of lichenicolous (lichen-inhabiting) species, none of which have previously been characterized in vitro or considered in molecular phylogenetic studies. We cultured Capronia peltigerae from Peltigera rufescens and report here the growth of this species on a variety of media and its phylogenetic position based on the analyses of nuclear ribosomal RNA, mitochondrial ribosomal RNA, and RNA polymerase II (RPB1) gene sequences. This species differs from the majority of Capronia studied in axenic culture in lacking a conidial anamorph. Phylogenetic analyses position C. peltigerae outside the Herpotrichiellaceae within a robustly supported basal lineage of the Chaetothyriales composed primarily of melanized, rock-inhabiting anamorphic fungi. Our results demonstrate that Capronia, as circumscribed currently, is polyphyletic, but they do not resolve the relationship of C. peltigerae with members of the Chaetothyriaceae.

Very few studies have addressed the diversity of culturable fungi from deep-sea sediments. We are reporting here the diversity of culturable fungi in deep-sea sediments of the Central Indian Basin obtained from a depth of ∼5,000 m. A total of 16 filamentous fungi and 12 yeasts isolated from 20 sediment cores of ∼35 cm length were identified by 18S and ITS sequencing of SSU rDNA. Most of the filamentous fungi were Ascomycota, while two were Basidiomycota. Microscopic identification of sporulating cultures mostly matched either with 18S or ITS sequences but seldom with both the sequences. Phylogenetic analysis of ascomycetes using 18S sequence data grouped them into 7 clusters belonging to Aspergillus sp., Sagenomella sp., Exophiala sp., Capronia sp., Cladosporium sp., Acremonium sp. and Tritirachium sp. ITS sequence data grouped isolates into 6 clusters belonging to Aspergillus sp., uncultured member of Hypocreaceae, Exophiala sp., uncultured soil fungus, Hypocreales and Trichothecium sp. The two basidiomycete isolates were a Tilletiopsis sp. evident from 18S as well as ITS sequence data. In contrast, most of the yeast isolates belonged to Basidiomycota and only one isolate belonged to the phylum Ascomycota. Sequences of 18S as well as ITS gave matching identification of most of the yeasts. Filamentous fungi as well as the yeasts grew at 200 bar/5°C indicating their adaptations to deep-sea conditions. This is the first report on isolation of Sagenomella, Exophiala, Capronia and Tilletiopsis spp. from deep-sea sediments. This study reports on the presence of terrestrial fungi as a component of culturable fungi in deep-sea sediments.

A phylogenetic study employing sequence data from the internal transcribed spacers (ITS1, ITS2) and 5.8S gene, as well as the 18S rRNA gene of various Cladosporium-like hyphomycetes revealed Cladosporium s. lat. to be heterogeneous. The genus Cladosporium s. str. was shown to represent a sister clade to Mycosphaerella s. str., for which the teleomorph genus Davidiella is proposed. The morphology, phylogeny and taxonomy of the cladosporioid fungi are discussed on the basis of this phylogeny, which consists of several clades representing Cladosporium-like genera. Cladosporium is confined to Davidiella (Mycosphaerellaceae) anamorphs with coronate conidiogenous loci and conidial hila. Pseudocladosporium is confined to anamorphs of Caproventuria (Venturiaceae). Cladosporium-like anamorphs of the Venturia (conidia catenate) are referred to Fusicladium. Human-pathogenic Cladosporium species belong in Cladophialophora (Capronia, Herpotrichiellaceae) and Cladosporium fulvum is representative of the Mycosphaerella/Passalora clade (Mycosphaerellaceae). Cladosporium malorum proved to provide the correct epithet for Pseudocladosporium kellermanianum (syn. Phaeoramularia kellermaniana, Cladophialophora kellermaniana) as well as Cladosporium porophorum. Based on differences in conidiogenesis and the structure of the conidiogenous loci, further supported by molecular data, C. malorum is allocated to Alternaria.

The nuclear small subunit rRNA genes of authentic strains of the black yeasts Exophiala dermatitidis, Wangiella dermatitidis, Sarcinomyces phaeomuriformis, Capronia mansonii, Nadsoniella nigra var. hesuelica, Phaeoannellomyces elegans, Phaeococcomyces exophialae, Exophiala jeanselmei var. jeanselmei and E. castellanii were amplified by PCR and directly sequenced. A putative secondary structure of the nuclear small subunit rRNA of Exophiala dermatitidis was predicted from the sequence data. Alignment with corresponding sequences from Neurospora crassa and Aureobasidium pullulans was performed and a phylogenetic tree was constructed using the neighbor-joining method. The obtained topology of the tree was confirmed by bootstrap analysis. Based upon this analysis all fungi studied formed a well-supported monophyletic group clustering as a sister group to one group of the Plectomycetes (Trichocomaceae and Onygenales). The analysis confirmed the close relationship postulated between Exophiala dermatitidis, Wangiella dermatitidis and Sarcinomyces phaeomuriformis. This monophyletic clade also contains the teleomorph species Capronia mansonii thus confirming the concept of a teleomorph connection of the genus Exophiala to a member of the Herpotrichiellaceae. However, Exophiala castellanii did not belong to this clade. Therefore, this species is not the anamorph of Capronia mansonii as it was postulated.

The anamorph life cycle of the black yeast Exophiala (Wangiella) dermatitidis is described. The fungus is dimorphic, yeast cells being the prevalent form of propagation. The fungus is strongly hydrophilic, probably completing its anamorph life cycle in submersion. Adaptation to dry conditions is slow. Types of conidiogenesis comprise annellidic, phialidic and sympodial reproduction, in addition to isotropic development. Phialoconidia fail to germinate under the conditions tested, and thus may have a function other than dispersal. Sterile, multicellular bodies resembling a Capronia teleomorph are described.

72 Strains belonging to 44 species of ascomycetous black yeasts were analyzed for their coenzyme Q systems. Prevalent were Q-10 and dihydrogenated Q-10 systems. Members of the Dothidealean suborder Dothideineae have Q-10(H2), while those belonging to the suborder Pseudosphaeriineae mostly have Q-10. The anamorph genus Exophiala Carmichael and the teleomorph genus Capronia Sacc. seem to be heterogeneous.